1. Field of the Invention
The present invention relates to computer-based tools for manipulating digital images. More specifically, the present invention relates to a method and an apparatus for locating a source sampling point within an image for an image-retouching tool.
2. Related Art
Unlike conventional film-based images, digital images can be loaded onto a computer system. This allows the digital images to be edited and otherwise manipulated by digital editing tools, such as image-retouching tools.
Image-retouching tools, such as a “clone stamp tool” or a “healing brush,” can be used to fix defects within an image, such as, dust, mold, film grain, etc. For example, a “clone stamp tool” allows a user to copy pixels from a source point in the image to a destination point in the image to cover up defects at the destination point. A “healing brush” also allows a user to copy pixels from a source point to a destination point, but it additionally fixes boundary transitions at the destination point to ensure that the copied pixels blend seamlessly with surrounding pixels at the destination point.
The process of using these image-retouching tools can be very time-consuming, because there are often a large number of small artifacts to be removed from an image. Furthermore, the quality of the result depends on the choice of a “source sampling point,” which is the location in the image from which pixels are copied by the image-retouching tool.
At present, the source sampling point for each defective area is selected through a time-consuming manual selection process. During this manual selection process, the user often has a hard time selecting an optimal source sampling point because the optimal source sampling points is often located very close to defective area. In practice, users have a difficult time identifying source sampling points in close proximity to defective areas, because they have to zoom in on the defective area, and because they have a hard time differentiating the source sampling point from the defective area.
Hence, what is needed is a method and an apparatus for locating source sampling points without the time-consuming manual process described above.